The problem is that I failed to build GHC anywhere. I was able to install binaries in machine where binaries are available, and that is all. When I try to install any thing from source or update from sources, I get messages like that:
zlib-0.5.4.2 failed during the building phase. The exception was:
>> ExitFailure 1
together with the suggestion:
(dist/package.conf.inplace) use 'ghc-pkg init' to create the database with
>> the correct format.
Of course, the suggestion does not work either. What amazes me is that Clean is practically dead (people do not improve the compiler since 2011), but it works flawlessly, without bugs, and it is very easy to build from sources. I don't like uniqueness types, but I am afraid that I will be forced into Clean.